The increased permeability of colicin-treated cells fails to correlate with the increased proportions of either cardiolipin or lysophosphatidylethanolamine. We have compared the permeability to CO ion of a mutant that produces excess cardiolipin and of mutants that fail to produce lysophosphatidylethanolamine with the permeability of colicin-treated wild type cells. we will separate the inner and outer membranes to locate the abnormal phospholipids, since only the inner membrane is thought to be a barrier to small molecules. Mutants lacking the membrane ATPase (uncA) do not reduce ATP levels when treated with colicin K, although they do become permeable and transport systems are inhibited. If the extracellular potassium concentration is high (0.1M), the colicin-treated uncA cells survive. We will use these permeable cells to explore the limits of intracellular ions and metabolites capable of supporting growth. The wild type ATPase appears to be activated by colicin treatment. We will examine the association of the ATPase with the membrane in colicin-treated cells in order to define how the colicin activates it. The association of concanavalin A with E. coli cells and membranes will be examined, particularly with regard to structural alterations leading to activation of phospholipase A. A method using concanavalin to separate the inner and outer membranes will be perfected.